Investigators from the areas of bioanalytical chemistry, organic synthesis, reproductive biology and physchobiology will collaborate on several problems of chemical communication in rodents. Both primer and selected signalling pheromones in urine will be investigated. Chemical analyses will be primarily based on glass capillary gas chromatography/mass spectrometry, selective detectors, other gas chromatographic ancillary techniques, as well as the most modern approaches to data treatment. Liquid chromatography will be employed for further purification and eventual isolation of the puberty-accelerating pheromone in mice; this effort will be supported by the available bioassay procedures. In studies of signalling pheromones (agression, fear, and sexual attraction), chemical identification studies will be correlated with behavioral assays. Organic synthesis will be carried out for both structural verification and biological assays of synthetic compounds.